Technetium Tc 99m Medronate Injection »Technetium Tc 99m Medronate Injection is a sterile,aqueous solution,suitable for intravenous administration,of sodium medronate and stannous chloride or stannous fluoride that is labeled with radioactive Tc 99m.It contains not less than 90.0percent and not more than 110.0percent of the labeled amount of Tc 99m as stannous medronate complex expressed in megabecquerels (microcuries or millicuries)per mLat the date and time indicated in the labeling.It may contain antimicrobial agents,antioxidants,and buffers.Other chemical forms of radioactivity do not exceed 10.0percent of the total radioactivity. Packaging and storage— Preserve in single-dose or multiple-dose containers at a temperature specified in the labeling. USP Reference standards á11ñ USP Endotoxin RS. Bacterial endotoxins á85ñ The limit of endotoxin content is not more than 175/VUSP Endotoxin Unit per mLof the Injection,when compared with the USP Endotoxin RS,in which Vis the maximum recommended total dose,in mL,at the expiration date or time. pHá791ñ: between 4.0and 7.8. Radiochemical purity— Not more than 10.0%of unbound Tc 99m (free pertechnetate),hydrolyzed Tc 99m,and technetium-tin colloid is present,determined as follows. System A— Under an atmosphere of nitrogen,place a measured volume of Injection,such that it provides a count rate of about 20,000counts per minute,about 25mm from one end of a paper chromatographic strip (see Chromatography á621ñ).Immediately develop the chromatogram over a suitable period by ascending chromatography,using sodium chloride solution (0.9in 100),and dry it under nitrogen.Determine the radioactivity distribution by scanning the chromatogram with a suitable collimated radiation detector.Hydrolyzed Tc 99m and technetium-tin colloid are located at the origin (RF0to 0.1). System B— Proceed as directed for System A,except to develop the chromatogram in dilute methanol (85in 100).Free pertechnetate is located at an RFof 0.6to 0.8.The sum of the percentage of radioactivity at the origin in System Aplus the percentage of radioactivity at an RFof 0.6to 0.8in System Bis not greater than 10.0%. Other requirements— It meets the requirements of the tests for Radionuclide identificationand Radionuclidic purityunder Sodium Pertechnetate Tc 99m Injection,and meets the requirements for Labeling,Biological distribution,and Assay for radioactivityunder Technetium Tc 99m Pyrophosphate Injection.It meets also the requirements under Injections á1ñ,except that it may be distributed or dispensed prior to completion of the test for Sterility,the latter test being started on the day of manufacture,and except that it is not subject to the recommendation on Volume in Container. Auxiliary Information— Staff Liaison:Andrzej Wilk,Ph.D.,Senior Scientific Associate Expert Committee:(RMI)Radiopharmaceuticals and Medical Imaging Agents USP28–NF23Page 1858 Phone Number:1-301-816-8305